ATF4 and cancer: Recent studies show PERK’s tumor-promoting activity in cancers such as ovarian carcinoma, where the persistent activation of the PERK-eIF2α-ATF4 signaling pathway promotes cancer cell survival, chemoresistance, and suppression of antitumor immunity via expansion and activation of myeloid-derived suppressor cells (Chen and Cubillos-Ruiz, 2021; He et al., 2024).